The Unbelievers say: "Why is not a sign sent down to him from his Lord?" Say: "Truly Allah leaveth, to stray, whom He will; But He guideth to Himself those who turn to Him in penitence,- 27 Those who believe and find peace in their hearts from the contemplation of God: Surely there is peace of heart in the contemplation of God!" 28 So those who believe (in the message of the Truth) and do good are destined for happiness and a blissful end. 29 Thus We send thee (O Muhammad) unto a nation, before whom other nations have passed away, that thou mayst recite unto them that which We have inspired in thee, while they are disbelievers in the Beneficent. Say: He is my Lord; there is no Allah save Him. In Him do I put my trust and unto Him is my recourse. 30 And even if there were a Quran with which the mountains were made to pass away, or the earth were travelled over with it, or the dead were made to speak thereby; nay! the commandment is wholly Allah's, Have not yet those who believe known that if Allah please He would certainly guide all the people? And (as for) those who disbelieve, there will not cease to afflict them because of what they do a repelling calamity, or it will alight close by their abodes, until the promise of Allah comes about; surely Allah will not fail in (His) promise. 31